Mechanical comparison of materials used for extra-capsular stabilisation of the stifle joint in dogs.
OBJECTIVE
The mechanical properties of three materials (No. 2 polypropylene, No. 5 polybutilate-coated multifilament polyester and 18, 27 and 36 kg test monofilament nylon leader material) commonly used for extra-capsular stabilisation of the stifle in dogs with cranial cruciate ligament insufficiency were determined. The ability of No. 5 polybutilate-coated multifilament polyester and 36 kg test monofilament nylon leader material, when placed as extra-capsular sutures, to mitigate cranial drawer was evaluated in hindlimbs of cadavers.


METHODS
An in vitro mechanical study.


METHODS
Seven pairs of hindlimbs harvested from adult greyhound dogs recently euthanased for other reasons.


METHODS
Samples of each material, including samples of 27 kg test leader material that had been sterilised by one of three methods (ethylene oxide, one or five cycles in an auto-clave), were loaded to determine tensile and stress relaxation properties. The effect of cyclic loading on a No. 5 polybutilate-coated multifilament polyester and 36 kg test leader material was also determined. Using the harvested hindlimbs, cranial drawer was measured before and after transection of the cranial cruciate ligament and on the first and twelfth cycle following extra-capsular stabilisation with either No. 5 polybutilate-coated multifilament suture or 36 kg test leader material.


RESULTS
Leader material was found to have the most suitable mechanical characteristics for use as extracapsular stabilisation of the cranial cruciate ligament deficient stifle. Of the sterilisation methods, ethylene oxide was found to have the least detrimental effects on the handling and material characteristics of the leader material. Stifles stabilised with 36 kg test leader material had significantly less drawer than those stabilised with No. 5 polybutilate-coated multifilament polyester suture.


CONCLUSIONS
Monofilament nylon leader material would appear to have suitable mechanical properties for extra-capsular stabilisation of the cranial cruciate ligament deficient stifle. If possible the material should be sterilised using ethylene oxide.
Lewis
D D
DD
Graduate School of Biomedical Engineering, University of New South Wales, Sydney.
Milthorpe
B K
BK
Bellenger
C R
CR
D000818:Animals; D016118:Anterior Cruciate Ligament / Q000502:physiology / Q000601:surgery; D001696:Biomechanical Phenomena; D002102:Cadaver; D004283:Dog Diseases / Q000503:physiopathology / Q000601:surgery*; D004285:Dogs; D005027:Ethylene Oxide; D007593:Joint Instability / Q000503:physiopathology / Q000601:surgery / Q000662:veterinary*; D009757:Nylons / Q000592:standards*; D011091:Polyesters / Q000592:standards*; D011126:Polypropylenes / Q000592:standards*; D013227:Steam; D013242:Sterilization / Q000379:methods; D013264:Stifle / Q000502:physiology / Q000601:surgery*; D013536:Suture Techniques / Q000592:standards / Q000662:veterinary; D013537:Sutures / Q000592:standards / Q000662:veterinary*; D016474:Weight-Bearing
D009757:Nylons; D011091:Polyesters; D011126:Polypropylenes; D013227:Steam; D005027:Ethylene Oxide